Osteoporosis (cont.)

William C. Shiel Jr., MD, FACP, FACR

Dr. Shiel received a Bachelor of Science degree with honors from the University of Notre Dame. There he was involved in research in radiation biology and received the Huisking Scholarship. After graduating from St. Louis University School of Medicine, he completed his Internal Medicine residency and Rheumatology fellowship at the University of California, Irvine. He is board-certified in Internal Medicine and Rheumatology.

Catherine Burt Driver, MD

Catherine Burt Driver, MD, is board certified in internal medicine and rheumatology by the American Board of Internal Medicine. Dr. Driver is a member of the American College of Rheumatology. She currently is in active practice in the field of rheumatology in Mission Viejo, Calif., where she is a partner in Mission Internal Medical Group.

Chemotherapy that can
cause early menopause due to its toxic effects on the ovaries

Amenorrhea (loss of the menstrual period) in young women
is associated with low estrogen and osteoporosis;
amenorrhea can occur in women who undergo extremely vigorous exercise training and in women with very low body fat
(for example, women with anorexia nervosa)

Immobility, such as after a stroke,
or from any condition that interferes with walking

Hyperthyroidism, a condition wherein too much thyroid hormone is produced by the thyroid gland (as in Grave's disease) or is ingested as thyroid hormone medication

Hyperparathyroidism is a disease wherein there is excessive parathyroid hormone production by the parathyroid gland, a small gland located near or within the thyroid gland. Normally, parathyroid hormone maintains blood calcium levels by, in part, removing calcium from the bone. In untreated hyperparathyroidism, excessive parathyroid hormone causes too much calcium to be removed from the bone, which can lead to osteoporosis.

When vitamin D is lacking, the body cannot absorb adequate amounts of
calcium from the diet to prevent osteoporosis. Vitamin D deficiency can result from lack of
intestinal absorption of the vitamin such as occurs in celiac sprue and
primary biliary cirrhosis.

Certain medications can cause
osteoporosis. These include long-term use of heparin (a blood
thinner), antiseizure medications such as phenytoin (Dilantin) and phenobarbital, and
long-term use of oral corticosteroids (such as
prednisone).